Learn HTML Geolocation API Code

Tips (Total 8)

1. What is HTML Geolocation API

2. How to create HTML Locate the User's Position

3. What type of browsers will support for HTML Geo Location

4. How to Use HTML Geolocation

5. How to add Handling Errors and Rejections

6. What is Location-specific Information

7. How to create HTML getCurrentPosition() Method - Return Data

8. How to create HTML Geolocation Object - Other interesting Methods

# Tips-1) What is HTML Geolocation API

The HTML Geolocation API is used to locate a user's position.

The HTML Geolocation is used to get the geographical position of a user. Due to privacy concerns, this position requires user approval. Geo-location in HTML5 is used to share the location with some websites and be aware of the exact location. It is mainly used for local businesses, and restaurants, or showing locations on the map. It uses JavaScript to give latitude and longitude to the backend server.

Most browsers support Geolocation API. Geo-location API uses a global navigator object. In this article, we will know HTML Geolocation, various properties, methods & their implementation through examples.

Syntax:

var loc = navigator.geolocation

Example of HTML Geolocation API

Try following Example

index.html

Example: HTML


<!DOCTYPE html>
<html>
 
<body>
    <p>Displaying location using Latitude and Longitude</p>
 
    <button class="geeks" onclick="getlocation()">
        Click Me
    </button>
    <p id="demo1"></p>
 
    <script>
        let variable1 = document.getElementById("demo1");
        function getlocation() {
            navigator.geolocation.getCurrentPosition(showLoc);
        }
        function showLoc(pos) {
            variable1.innerHTML =
                "Latitude: " +
                pos.coords.latitude +
                "<br>Longitude: " +
                pos.coords.longitude;
        }
    </script>
</body>
   
</html>

# Tips-2) How to create HTML Locate the User's Position

The HTML Geolocation API is used to get the geographical position of a user.

Since this can compromise privacy, the position is not available unless the user approves it.

Note: Geolocation is most accurate for devices with GPS, like smartphones.

Try GEO Location

Follow the Example

index.html

Example: HTML

<p><button class="w3-btn w3-blue w3-round" onclick="getLocation()">Try It</button></p>
<div id="mapholder"></div>
<script src="https://maps.google.com/maps/api/js?key=AIzaSyBu-916DdpKAjTmJNIgngS6HL_kDIKU0aU"></script>
<script>
var x=document.getElementById("demo");
function getLocation()
  {
  if (navigator.geolocation)
    {
    navigator.geolocation.getCurrentPosition(showPosition,showError);
    }
  else{x.innerHTML="Geolocation is not supported by this browser.";}
  }

function showPosition(position)
  {
  var lat=position.coords.latitude;
  var lon=position.coords.longitude;
  var latlon=new google.maps.LatLng(lat, lon)
  var mapholder=document.getElementById('mapholder')
  mapholder.style.height='250px';
  mapholder.style.width='100%';

  var myOptions={
  center:latlon,zoom:14,
  mapTypeId:google.maps.MapTypeId.ROADMAP,
  mapTypeControl:false,
  navigationControlOptions:{style:google.maps.NavigationControlStyle.SMALL}
  };
  var map=new google.maps.Map(document.getElementById("mapholder"),myOptions);
  var marker=new google.maps.Marker({position:latlon,map:map,title:"You are here!"});
  }

function showError(error)
  {
  switch(error.code) 
    {
    case error.PERMISSION_DENIED:
      x.innerHTML="User denied the request for Geolocation."
      break;
    case error.POSITION_UNAVAILABLE:
      x.innerHTML="Location information is unavailable."
      break;
    case error.TIMEOUT:
      x.innerHTML="The request to get user location timed out."
      break;
    case error.UNKNOWN_ERROR:
      x.innerHTML="An unknown error occurred."
      break;
    }
  }
</script>

# Tips-3) What type of browsers will support for HTML Geo Location

The numbers in the table specify the first browser version that fully supports Geolocation.

Note: As of Chrome 50, the Geolocation API will only work on secure contexts such as HTTPS. If your site is hosted on an non-secure origin (such as HTTP) the requests to get the users location will no longer function.

# Tips-4) How to Use HTML Geolocation

The getCurrentPosition() method is used to return the user's position.

The example below returns the latitude and longitude of the user's position:

Example of using HTML GEO LOCATION

Try following Example

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body>
<h1>HTML Geolocation</h1>
<p>Click the button to get your coordinates.</p>

<button onclick="getLocation()">Try It</button>

<p id="demo"></p>

<script>
const x = document.getElementById("demo");

function getLocation() {
  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(showPosition);
  } else { 
    x.innerHTML = "Geolocation is not supported by this browser.";
  }
}

function showPosition(position) {
  x.innerHTML = "Latitude: " + position.coords.latitude + 
  "<br>Longitude: " + position.coords.longitude;
}
</script>

</body>
</html>

Output should be:

Example explained:

Check if Geolocation is supported
If supported, run the getCurrentPosition() method. If not, display a message to the user
If the getCurrentPosition() method is successful, it returns a coordinates object to the function specified in the parameter (showPosition)
The showPosition() function outputs the Latitude and Longitude

The example above is a very basic Geolocation script, with no error handling.

# Tips-5) How to add Handling Errors and Rejections

The second parameter of the getCurrentPosition() method is used to handle errors. It specifies a function to run if it fails to get the user's location:

Example of Handling Errors and Rejections

The second parameter of the getCurrentPosition() method is used to handle errors. It specifies a function to run if it fails to get the user's location:

index.html

Example: HTML

<button onclick="getLocation()">Try It</button>

<p id="demo"></p>

<script>
const x = document.getElementById("demo");

function getLocation() {
  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(showPosition, showError);
  } else { 
    x.innerHTML = "Geolocation is not supported by this browser.";
  }
}

function showPosition(position) {
  x.innerHTML = "Latitude: " + position.coords.latitude + 
  "<br>Longitude: " + position.coords.longitude;
}

function showError(error) {
  switch(error.code) {
    case error.PERMISSION_DENIED:
      x.innerHTML = "User denied the request for Geolocation."
      break;
    case error.POSITION_UNAVAILABLE:
      x.innerHTML = "Location information is unavailable."
      break;
    case error.TIMEOUT:
      x.innerHTML = "The request to get user location timed out."
      break;
    case error.UNKNOWN_ERROR:
      x.innerHTML = "An unknown error occurred."
      break;
  }
}
</script>

Output should be:

# Tips-6) What is Location-specific Information

This page has demonstrated how to show a user's position on a map.

Geolocation is also very useful for location-specific information, like:

Up-to-date local information
Showing Points-of-interest near the user
Turn-by-turn navigation (GPS)

# Tips-7) How to create HTML getCurrentPosition() Method - Return Data

The getCurrentPosition() method returns an object on success. The latitude, longitude and accuracy properties are always returned. The other properties are returned if available:

Property	Returns
coords.latitude	The latitude as a decimal number (always returned)
coords.longitude	The longitude as a decimal number (always returned)
coords.accuracy	The accuracy of position (always returned)
coords.altitude	The altitude in meters above the mean sea level (returned if available)
coords.altitudeAccuracy	The altitude accuracy of position (returned if available)
coords.heading	The heading as degrees clockwise from North (returned if available)
coords.speed	The speed in meters per second (returned if available)
timestamp	The date/time of the response (returned if available)

# Tips-8) How to create HTML Geolocation Object - Other interesting Methods

The Geolocation object also has other interesting methods:

watchPosition() - Returns the current position of the user and continues to return updated position as the user moves (like the GPS in a car).
clearWatch() - Stops the watchPosition() method.

The example below shows the watchPosition() method. You need an accurate GPS device to test this (like smartphone):

Example of Geolocation Object - Other interesting Methods

Follow the Example

<button onclick="getLocation()">Try It</button>

<p id="demo"></p>

<script>
const x = document.getElementById("demo");

function getLocation() {
  if (navigator.geolocation) {
    navigator.geolocation.watchPosition(showPosition);
  } else { 
    x.innerHTML = "Geolocation is not supported by this browser.";
  }
}
    
function showPosition(position) {
    x.innerHTML="Latitude: " + position.coords.latitude + 
    "<br>Longitude: " + position.coords.longitude;
}
</script>